While ovulation induction with human menopausal gonadotropins (hMG) is commonly used to treat refractory ovulatory disorders, little is known about the characteristics of multiple consecutive treatment cycles. Since such cycles may be required to achieve pregnancy, it is important to ensure that the ovarian response is not compromised during consecutive cycles. We examined the ovarian response and cycle characteristics of 25 women with World Health Organization (WHO) group II ovulatory disorders who underwent three consecutive ovulatory hMG cycles. The total hMG dose and duration of treatment increased significantly between the first and third consecutive hMG cycles, although the final estradiol levels remained similar. While the mean numbers of follicles > or = 14 mm in diameter were comparable, the size of the largest follicle was significantly greater during the third cycle as compared to the first. These results suggest that while the ovary required more vigorous stimulation during subsequent cycles, the ultimate hormonal and follicular response did not appear to be compromised during this series of three consecutive cycles.